Colored gasoline



Patente Sept. 29, 1931 nan STATES GELLEBT ALLEMAN, OF SWARTHMORE, PENNSYLVANIA, ASSIGNOR TO SUN OIL COM- PANY, OF PHILADELPHIA,

PENNSYLVANIA, A CORPORATION OF NEW JERSEY COLORED GASOLINE No Drawing. Application filed July 28,

In the sale of gasoline at retail under a trade-mark, or as the advertised product of a particular manufacturer, it is important that the a product or which he asks. Unless, however, the manufacturer operates his own filling stations, there is nothing to prevent an unscrupulous retailer from substituting a cheaper and inferior gasoline, thereby dam- BU aging the reputation of the manufacturer and inflicting upon him serious loss, the extent of which it is difiicult to compute.

The prevention of this substitution of inferior gasoline for superior gasoline by imparting to the gasoline a peculiar and distinctive color which it will be difficult or practically impossible for the vendor to impart to any uncolored gasoline is one of the objects of the invention. This problem presents serious difficulties. The color must not be one which will impart any cloudy appearance to the gasoline. The color must not be one that characterizes inferior gasoline, or which is. rightly or wrongly, associated, in the mind of the purchasing public, with inferior gasoline. The color must be fast; that is, must not change on exposure to light or during storage for a shorter or longer time. The gasoline should not be colored with,a dye that, if the gasoline is used for dry cleaning, will impart an objectionable color to the garments. The color must also be insoluble in water for reasons hereinafter stated. The gasoline must be carefully refined in order to prevent an otherwise fast color from being ineffective to maintain the color imparted by the gasoline. 7

The coloring of petroleum products by ,0 means of different dyes and coloring matters is well known. Most of these colors or dyes, when mixed with oil, will, when water is subsequently added, leave the oil, in whole or in part, and go into the water. Some of urchaser shall receive the precise 1928. Serial No. 296,101.

the known colors or dyes impart an objectionable color to the gasoline. Some of the' .of such colors, however, and very few are available that will respond, even in degree, to the requirements hereinbefore mentioned. Among the colors meeting the above requirements which heretofore have never been successfully imparted to gasoline is a blue color. This color is, on the whole, the most' desirable, not only because no inferior gasoline has this color, but also because the color is not suggestive of inferiority in the mind of the public.

Many efiorts have been made, without success, to secure a gasoline of this color that will have no objectionable characteristics. In most instances, where gasoline has been satisfactorily colored blue in the first instance, it turns to a green, or greenish blue, or yellow, upon exposure to sunlight or after storage.

After experimenting with and thoroughly testing a great number of colors, I have discovered certain colors that impart to the gasoline the desired blue color and that, in maximum degree. meet all the requirements above enumerated. These colors are derivatives of indigo, specifically certain brominated derivatives or mixtures of brominated derivatives .of indigo, and more particularly a mixture of 4.5.7.4 .5 .7 hexabromindigo together with 4.5.7.5.7' pentabrom indigo, commercially known as durindone blue 6 B,

the hexabromindigo having the structural formula Bl 4 NH NH and the pentabromindigo having the structural formulathe hexabrom compound usually being present in a greater proportion than the pentabrom compound, and the mixture usually containing a small proportion of tetrabromindigo (5.7.5.7).

This color has also the advantage that it has the maximum coloring efi'ect sought when used in the proportion of about one gart in about 200,000 parts of gasoline.

asoline so colored is a beautiful blue free from any cloudy effect. It is so reliably fa st that it does not change color when exposed to sunlight for a prolonged period.

The specific color compound desired is a dark blue powder, readily soluble in xylene, benzene, carbon tetrachloride, chloroform, and amyl acetate. It is less soluble in gasoline and almost insoluble in ethyl and in methyl alcohol.

It Is insoluble in water.

Its spectrum in xylene ranges in accordance with the percentage of the various components present.

Its insolubility in water is an important characteristic. Most dyes, when mixed with oil, will, when water is subsequently added, leave the oil, in whole or in part, and go into the water. A color that cannot be washed out with water has the additional advantage that it insures against the addition of water to the gasoline, because, if water be added thereto, the buyer can see the water, as a transparent mass against a blue background, flowing through the glass on the pump.

Theproportion of the various brominated derivatives of indigo present in the described color determines the intensity and the shade of the blue color of the solution.

The pure hexabrom derivative of indigo yields a pure deep blue color. As the proportion of the pentabrom indigo is increased, the color of the solution shades from blue to violet. If more than a trace of tatrabrom indigo ispresent in the solution, the

.violet color is intensified.

It will be understood that other halogenated derivatives of indigo having similar and solubility may be employed.

As examples, 5.7.5 .7 dichlordibrom indigo; 5.7.5 .7 tetrachlorindigo; 4.5.4 .5 dichlordibrom indigo may be employed with good results, but are-less preferable.

It should be understood, however, that the gasoline, when colored with the colors herein described, may not retain the desired color unless, as hereinbefore stated, the gasoline is carefully refined and is substantially water-white in color. Refined gasoline having a yellow tinge will produce a green product. Even if the refined gasoline has no yellow tinge, still, if it is not properly refined, it will become yellow on standing and will eventually turn green. There is, in fact, probably only a minor percentage of gasoline commonly manufactured that will lend itself to being blended with the above color for the purpose of producing blue gasoline.

An example of a process that has been successfully employed for manufacturing water-white gasoline to which a blue color may be permanently imparted by means of the above mentioned dye is the process set forth in the Thomas Patent No. 1.624592,

dated April 12. 1927, for Process of manu' facturing gasoline.

It is preferred to add the color to the gasoline by dissolving it in a small quantity of benzol and gradually adding the concentrated solution to the quantity of gasoline intended to be colored. This procedure follows known methods of adding colors or of a mixture of brominated derivatives of indigo.

5. A colored gasoline comprising commercial gasoline containing a small proportion of hexabromindigo.

6. A colored gasoline comprising commercial gasoline containing a small proportion of a mixture of hexabromindigo ($5.74.- 5.7) and of pentabromindigo (4.5.7.5'.7).

7. A colored gasoline comprising commercial gasoline containing a small proportion of a mixture of hexabromindigo (4.514.- 5.7') and of pentabromindigo (4.5.7.5'12) together with a, smaller proportion of tetrabromindigo (5.7.5 .7

In testimony of which invention, 1 have hereunto set my hand, at Swarthmore, Pennsylvania, on this 26th day of July; 1928.

GELLERT ALLEMAN. 

